A loss is a trade that went against you. Costs are what you pay on every trade, winners included: spread, slippage, commission, financing. Losses depend on direction, costs do not. That is why a run of winners can still end up negative.
| Criterion | Loss | Trading costs |
|---|---|---|
| Occurs on | Losing trades | Every trade |
| Depends on | Direction and stop distance | Number of trades, size, holding time |
| Visible | As a red line in the journal | Mostly only in the statement, the spread nowhere |
| Components | Price difference | Spread, slippage, commission, funding or swap |
| Controlled by | Stop and position size | Fewer trades, liquid hours, limit orders |
| Example | 10 winners at 5 each: plus 50 | 10 times 6 in costs: minus 60, net minus 10 |
When you evaluate a single setup: risk, loss in R, stop discipline.
When you evaluate a strategy over 100 trades. In scalping costs are often the biggest item, in swing trading overnight financing dominates.
Why do I not see the spread in my statement?
Because it is built into the entry price. You buy at the ask and sell at the bid, so every position starts slightly negative. It only becomes visible if you record it in the journal yourself.
Educational content, not investment or tax advice. Neutrally contrasted, not a recommendation of either approach. Trading leveraged products carries risk of total loss.